This is at the core of the issue. Making laws based solely on religious beliefs is blatantly unconstitutional. Yet, oddly, the people who crow the loudest about many things being unconstitutional are the very ones wanting their religious views to be part of the law in this case.
The ones who want homosexual marriage, something that has never been part of our great country, are the ones pushing their beliefs on others. Christian views have been around since time began, when God spoke, and created.